Tackling leakage

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Tackling leakage is the number one priority for us and for our customers.

We have 20,000 miles of water pipes across London and the Thames Valley, serving more than 2000 litres a week of water on average to each of our 9 million customers.

That's 2,600 million litres a day - the equivalent of filling 2,600 Olympic size swimming pools.

To ensure we continue to provide the essential service to you and keep on top of leakage, we have to continually maintain these pipes.

In London and some parts of the Thames Valley many pipes are made of cast-iron and have been in the ground for more than 150 years. So, in addition to maintenance, we also have to replace the old ones that are prone to leaks and bursts.

Our work so far

Since privatisation 26 years ago, we have invested over £11bn in upgrading our ageing infrastructure to reduce leaks and bursts and improve services to you.

Over the past decade we have replaced over 1,600 miles of cast-iron Victorian water mains with tough new plastic pipes less prone to leaks and bursts.

This has helped us beat our leakage targets for the past nine years, cutting leakage by 13 per cent over the past five years.

In the next five years, from 2015 to 2020, we’ll be investing almost £5bn more to continue our upgrade of water pipes, sewers and other facilities.

Replacing London's Victorian water pipes

Winter challenges

Freezing weather conditions like those we experienced in January 2013 mean that we have to work even harder to stay on top of leakage.

Our pipes, especially the old cast-iron ones burst more when the water in our reservoirs cools below 5 degrees C. When this water goes through the pipes, it makes them shrink and where there are hairline weaknesses, they can break.

In such cases, the number of leaks and bursts can quadruple, so we have to plan ahead to ensure that we are well-placed to cope with the challenge when it arrives.

The process of repairing a leak

Keeping on top of things

As well as tackling the visible leaks, we have a targeted programme across London and the Thames Valley to find 'sneaky leaks'.

If left unchecked, they can soon become big, visible bursts so by fixing them before they get worse, we hope to minimise really serious disruption.

Inevitably, our work will cause some disruption to road users and residents, for which we apologise in advance, but this is must-do work so please bear with us.

Reporting leaks or bursts

If you see a leak or burst, please don't assume we know about it.

Report a leak or burst

Also in this section

Leaks at Your Property

Report a Leak or Burst Pipe

How We Repair Leaks